Ballast tamping machine for railways



Sept. 27, 1949. F. H. PHILBRICK 2,482,796

BALLAST TAMPING MACHINE FDR RAILWAYS Filed Aug. 15, 1947 4 Shees-$heet 1 Sept. 27, 1949. F. H. PHILBRICK 5 BALLAST TAMPING MACHINE FOR RAILWAYS Filed Aug. 15, 1947 I 4 Sheets-Sheet 2 p 1949- F. H; PHILBRICK' 2,482,796

BALLAST TAMPING MACHINE FOR RAILWAYS Filed Aug. 15, 1947 4 Sheets-$heet 3 p 27, 1949- F. H; PHILBRICK 2,482,796

BALLAST TAMPING MACHINE FOR RAILWAYS Filed Aug, 15, 1947 4 Sheets-Sheet 4 UNITED STATES PATENT OFFICE BALLAST TAMLPING MACHINE FOR RAILWA Frank H. rum-mi, Evanston, 111.

Application August 15, 1947, Serial N0. 768,890

18 Claims. 1

The invention relates to machines for tamping or packing ballast under and between railway ties and more particularly to mechanism for automatically feeding the ballast deposited at the outer sides of the rails into the cribs between the ties.

Heretofore in the operation of ballast tamping machines of the type in which the tamping elements for packing the ballast under and between the ties are mounted on a drop-head for imparting hammer strokes to the elements, it has been necessary to provide operators for manually shoveling the ballast into the path of the tamping elements between the cribs after the ballast dumped into the cribs has been packed.

The primary object of the present invention is to provide apparatus for automatically feeding or shoveling ballast deposited at the outer sides of the rails, or adjacent the outer ends of the ties, transversely into the cribs where the tamping elements will pack the ballast under and between the ties. By thus automatically feeding the ballast the tamping operations are expedited and labor involved in manually shoveling the ballast is saved.

Another object of the invention is to provide improved mechanism for automatically feeding ballast from the outer sides of the rails into the cribs and to the tamping elements which is adapted for operation with a tamplng machine of the drop hammer type.

Another object of the invention is to provide improved mechanism for shoveling ballast from the road bed adjacent the outer ends of the rails into the cribs between the ties after ballast delivered into the cribs has been packed around the ties, for supplying the additional ballast necessary for filling the cribs.

A still further object of the invention is to provide automatic feeding mechanism of this type which is simple in construction and emcient in' operation.

Other objects of the invention will appear from the detailed description.

The invention consists in the several novel featureshereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings:

Figure 1 is a transverse section taken on line l-l of Fig. 3 of a ballast tamping machine equipped withthe apparatus for automatically feeding ballast into the cribs, parts being shown 2 Fig. 3 is a longitudinal section-taken on line 3-3 of Fig. 1;

Fig. 4 is a transverse section illustrating the ballast shoveling apparatus and a portion of the drop-head;

Fig. 5 is a side elevation of one of the devices for controlling the pneumatic operation of the shovels for feeding ballast into the cribs, the frame plates on which the devices are mounted being shown in section;

Fig. 6 is a section taken on line 6-8 of Fig. 5, parts being shown in elevation;

Fig. 7 is a detail of the cam lever for shifting the air valve for controlling the operation of the shovels;-

Fig. 8 is a side elevation of the machine illustrating the shoveling. devices at one side of the machine; and

Fig. 9 is a detail illustrating one pair of shovels and its shifting mechanism, parts being shown in section.

The invention is exemplified on a truck or car which comprises a truck-frame generally designated In which is supported on traction-wheels II which are adapted to travel on the rails a of a railway track. The truck is equipped with an internal combustion motor, a transmission for driving the truck wheels, and gearing for operating the drop-head on which the tamping elements are mounted as will be understood in the art and as exemplified in my application filed October 1, 1945, Serial No. 619,585, and in my application No. 768,301, filed August 13, 1947.

The tamping elements are mounted on a drophead, generally designated l6, which extends transversely of the truck and is mounted to slide vertically in channels I! which are fixedly sup ported on side-plates I! of frame Ill. Head I6 functions as a drop hammer for operating the tamping elements for packing the ballast under the ties b on which the rails a are laid. The upper portions of frame In are rigidly connected by channel beams 22. The frame In includes longitudinal side beams H and transverse beams ll which are spaced apart for the operation between themof the head Iii and the tamping elements carried thereby. Head i6 is liftable by power derived from the motor on the truck through mechanism which lifts said head and then releases it for a drop hammer stroke. This mechanism comprises a transverse shaft 24 which is continuously driven from the motor by suitable gearing (not shown) and journalled in bearing brackets 26 which are supported on a cross beam 28 of the frame structure, a pair of s eaves sprocket wheels which are fixed to shaft 24, a pair of idler sprockets 38, and sprocket chains 33 between vertically aligned sprockets 30 and 3B. Intermittent lifting strokes are imparted to head It from shaft 24 by rollers 33 which are mounted at the outer sides of link chains 33 and are adapted to intermittently engage abutments 39 which are fixed to and project from one side of drop-head l5. Each idler sprocket 36 is journalled on a forked bell-crank lever 31 which is fulcrumed at 3| on the truck frame and is urged to keep its chain 33 taut by a spring 42 applied to the upstanding arm on said lever. The transversely aligned rollers 38 of chains 33 during their upward travel will intermittently engage abutments 39 and lift head It until said rollers pass of! said abutments at the end of an up-stroke and will then release head [3 for a hammer stroke to the tamping elements carried thereby. This exemplifies power mechanism for intermittently imparting lifting strokes. to head It and the tamping elements and dropping them to impart hammer strokes to the tampin elements.

A gang of tamping elements or tools is provided at each side of head it. Two elements of each gang operate between the track-rails and the other two operate outwardly of said rails. These elements are exemplified :by heads 46 which are provided with depending teeth 50. The elements of each gang are co-axially fulcrumed on pins 41 each of which is supported in a pair of cars on the outer end of a plate 49 which is on and integral with the lower end of head I 6. The tamping elements of the gangs on opposite sides of head l6 are disposed in opposed relation of one another and descend on opposite sides of a tie b to swing toward each other for packing the ballast in the cribs and under the ties. Each tamping element is provided with an integral arm 51 which extends upwardly from its fulcrum pin 41. The arms 51 of each pair of elements disposed transversely of the transverse center of the track are rigidly connected by a shaft 53.

The pivotal or angular movements of each gang of tampers are controlled during the full drop and lifting strokes by mechanism which comprises a single track structure and a roller 64 engaging said structure. Each roller 64 is carried by a shaft 55 which is mounted and supported in the low-er end of a pair of links 58, the upper ends or which are connected by pivot pins 53 to'lugs which are integral with head I5. Each roller shaft 56 is connected by links 63 to the inner ends of the shafts 53 of one gang of tampers. ally connected to a roller-shaft 56 and its outer end is pivotally connected on one of the shafts 53. Rollers 54 and the track structure are disposed at the transverse center of head I6 and each roller is positively guided during the full stroke of head It for controlling the angular movement of the tampers. This track structure, generally designated 66, includes inner and outer rails for each roller 64 at opposite sides of head I5. This track structure includes a central post 10, the opposite faces of which form inner rails II for rollers 64 respectively, and outer rails- 12. Each roller -64 is confined between an inner rail II and an outer rail 12 for positively controlling the angular movements of the tamping elements during the full stroke of head It.

The upper portions of each inner rail II and outer rail 12 are substantially vertical and parallel for guiding rollers '54 rectilinearly and vertically during the upper portion of each stroke The inner end of each link 68 is pivotof head It. The lower portions of each pair of rails 1 IV and I2 are curved or offset as at Ila and 12a for causing the rollers 34 on opposite sides of head 16 to spread apart during the lower portion of each stroke of the head for operating the links 58 and shafts 53 to simultaneously rock the arms 51 outwardly to swing the lower ends of the tampers inwardly and angularly as the head approaches the lower end of its stroke and so as to rock the tampers in the opposite direction during the initial portion of each up-stroke of the head. The track structure is formed of plate metal or bars. A screw engages a bridge plate 8| for adjustably supporting the track structure for vertical adjustment of the track structure for the operation of the tampers with railway rails of diiferent heights. The sides of the track structure are adjustably supported on frame I0 by vertical rods 15 the lower ends of which are welded to the track structure, and nuts 18 which are screw threaded to the upper ends of rods 16 and engage the upper ends of channel bars 19 which are welded to the track structure and sleeves 19a which are welded to cross-beams of the truck frame. By adjusting nuts 18 the entire track structure may be adjusted vertically to vary the angular movements of the tampers relatively to rails a of different heights.

The operation of the tamping mechanism will be as follows: The truck or car is moved on the railway track so that the gangs of tampers will be positioned to straddle the tie with the head It positioned centrally above a tie. The power mechanism will then be operated to intermittently lift head l6 and then release it' for drop hammer strokes. Rollers 54 and their link connections with shafts 53 will control the angular movements of the tamping elements. During the initial portion of each drop-stroke the vertical portion of track 12 will cause the rollers 64 to travel vertically and rectilinearly between the upper straight portions of the tracks and the tampers will be shifted bodily with head It through fulcrum shafts l1. Toward the end of each drop stroke of the head l5, rollers 64 will engage the offset or cam portions 1 I of the track structure and shift apart so that links 68 will operate shafts 53 and arms 52 to impart angular movement to the tampers on the axes of fulcrum shafts 41. This angular movement of the tampers will be continued until the teeth 50 thereon have packed the ballast under the tie and into the cribs. The path of the teeth is indicated by dotted lines a: in Fig. 3. During the commencement of the lifting stroke of head It, the tampers will be positively angularly shifted in reverse directions by rollers 54 and the offset or cam portions 12a of the trackstructure until said rollers pass between the straight upper portions of said tracks. During the remainder of the up-stroke of head it, roller 54 will travel rectilinearly and the tampers will be shifted bodily without angular movement. The ballast will be progressively delivered into the crib until the tampers pack suflicient ballast under and between the ties to fill the crib.

The mechanism for automatically feeding or shoveling ballast into the path of movement of the tamping elements during the progressive packing of the ballast into the cribs comprises a pair of shovels or tools, generally designated 80, which are transversely aligned with the cribs and positioned beyond the ends of the tie when the tamping elements are positioned to pack ballast at the sides of a tie. A pair of shovels 8 is provided at each side of the truck frame i'or simultaneously shoveling or feeding ballast deposited near both ends of a tie transversely into ment. The mechanism for operating each pair of shoes 8| comprises an arm 88 fixedly secured to one end of shaft 83 and a fluid pressure operated device which includes a cylinder 81 which is pivotally supported at 88, and a stem 88 on a piston which is slidable in cylinder 81 and 1s pivotally connected at 88 to the distal end of arm 86. When fluid, for example, air under pressure, is admitted to cylinder 81, the piston will be operated to shift stem 89 and rock arm 88, shaft 83, arms 82 and shoes 8| to shovel a batch of ballast from the supply at the ends of the ties into the cribs at the opposite sides of one tie. A

spring 9| is connected to stem 88 and the frame structure for retracting the piston in cylinder 81 and shovels operable thereby. An elastic bumper 92 is confined in a bracket 93 on a hanger 85 for arresting stem 89 at the end of its outward stroke. Each shoe BI is pivotally connected by a pin 98 to its arm 82 and a spring 95 is applied between said. shoe and arm 82 to normally hold the shoe against an abutment 88 on arm 82 during the in-strokes of the shovels and to permit the shoes to swing inwardly during the out-strokes of the shoe. This exemplifies fluid pressure operable devices for operating the shovels for feeding ballast into the cribs where it will be packed by the tamping elements.

The lead shovel 88 of each connected pair has, as illustrated in Fig. 18, a somewhat shorter effective radius, than its trailing shovel so that the lead shovel will displace a portion of the ballast from the pile at one side of the road bed into the crib at the lead side of the tie and the trailing shovel will displace the remainder of the pile into the crib at the trailing side of the tie.

The operation of shovels 88 is automatically controlled to impart thereto an in-stroke during an up-stroke of the drop-head I8 and the tamping elements. The fluid operable device for each pair of shovels at one side of the machine is operable by compressed air from a reservoir 98 which is mounted on the truck frame. Each pair of shovels is controlled by a valve, generally designated 98, and secured on the frame structure and periodically operated by means on the drop-head I6, for controlling the flow of compressed air to each cylinder 81 and the exhaust of air therefrom. Each valve 89 includes a valvemember I 88 in valve casing IN, a stem I82 for valve-member I88, a lever I83 which is fulcrumed at I84 on casing IIlI and provided with a cam I85 for shifting stem I82 and an arm I86. A pair of opposed springs I81 are connected to one end of each lever I 88 and to the frame structure for normally holding the lever in its centralized position and permitting valve member I88 to cut off the delivery of air to the cylinder 81. A pipe 98' supplies air from reservoir 88 to a chamber in casing I8I which is normally closed by valve member I88. A pipe I 88, communicatively connects a chamber in casing MI and a cylinder 81. A normally open valve member I88 on stem I82 controls the exhaust of air from pipe I 88 and cylinder 81 through a port I89 to atmosphere.

' tralized position by oneoi the springsfi81, During the up-stroke of drop head I8, .studI-I8 will-- engage arm I88.- and rock le'ver I83 to open; 'yalve Arm I88 of lever I83 is operable by a stud H8 which is adjustably connectedto abar l II which is fixedly secured to'one face-oi drop-head I8 A slot H2 in bar III. permits vertical adjustment of the stud II8. During; the down-stroke of head I8, stud II81will engage .arm" I88 and rock lever I83 in. one directionto move camI85 away irony valve stem I'82.so that: spring, II 3-will 'hold vaive member I88 closedi'Aiter stud II 8 passes below arm I88, lever I88 willbe returnedtoitscenmember I88 and close valve member I88'", which will cause compressed-air to'ilow irom reservoirs '88 via pipe 88' past valve ."member 188 .and-

through pipe I88 to cylinder 81' and simultaneously close valve me'mberil'88. tocutioif the exhaust port I88. The compressed air in cylinder 81 will operatestem 89 to impart an iii-stroke.

. to the shovel 88 connected'thereto. When, the

stud II8'passes off arm I.86-during theup-str'okeof drop-head I8. one of the springs I81 will-restore lever I'83 to its normal position which will shift cam I85 to release valve stem I82 to simul-' taneously close valve member I88 and cut off the supply of air to pipe I88 and simultaneously open valve member I88 to exhaust air from cylinderfilling them during the succeeding strokes of the tamping elements. During the initial strokes of the tamping elements while the ballast deposited in the cribs is being packed, the shovels 88 will remain idle. The studs II8 on the drop-head I8 are located so that they will not pass under levers I83, until the tamping elements drop below a predetermined level and the ballast has been packed to a level between the ties which permits the head I6 to drop sufliciently to pass under arm I86 of lever I83. When that occurs, studs II8 during the succeeding up-stroke will operate levers I83 to control valves 98 for the operation of shovels 88. In practice, a single strokeof the shovels is usually sufiicient to displace the additional ballast necessary to complete the filling of This control mechanism for thethe cribs. operation of the shovels exemplifies means controlled by the depth of movement of the drophead I6 and the tamping elements, which varies as the ballast dumped into the cribs becomes packed therein. In other words, the shovels 88 remain idle until the ballast in the cribs has been packed suiliciently to require additional ballast for and tamping it in the cribs until they are filled to the desired height.

The operation of the apparatus for shoveling ballast into the cribs will be as follows: The machine is spotted on the track for the operation of the tamping elements on opposite sides of the tie and the shovels 88 at the opposite sides of the truck frame will then be positioned to transversely displace ballast from the road bed adjacent the ends of the tie into the cribs. The cribs are loaded with loose ballast which is usually the ties. During the initial strokes of drop-head I. the loose ballast in the cribs will be packed therein and the down-strokes of the tamping elements will be retarded by the ballast so that studs IIO will not pass below arms I06 of levers I03 and the shovels will remain idle. As loosely deposited ballast in the cribs in progressively packed by the tamping elements, the down strokes of head I6 and said elements will be lengthened sufllciently to cause valves 99 to deliver compressed air into cylinders 81 for imparting operative in-strokes to shovels 80 and displacing ballast from the piles at the sides of the track into position in the cribs to be packed by succeeding strokes of the tamping elements until the crib is filled with packed ballast. During each operative stroke of shovels 80, the short lead shovel of each connected pair will displace a portion of the pile of ballast from one side of the road bed into one crib and the following shovel will displace the remainder of the pile into the following crib. Normally valves 99 cut off the supply of air to cylinders 81 and exhaust air therefrom. During each down-stroke of head \IG which is sufllcient for studs IIO to pass under arms I06, the studs during the succeeding lifting stroke will swing levers I03 so that cams I05 will shift valve stems I02 to open valve members I00 for delivering compressed air to cylinders 81. As head I8 continues to the end of its lifting stroke, studs IIO will release levers I03 and permit springs I01 to restore said levers to their normal centralized position to cut oil the supply of air to cylinders 01 and to exhaust air therefrom. During the initial tamping operation of the ballast dumped into the cribs, the shovels will remain idle until the ballast has been packed sufllciently to require additional ballast from the piles at the sides of the road bed for filling the cribs.

During the operation of the shovels 00 the lead shovel at each side of the track, having a shorter radial length, will displace only a portion of the ballast deposited in wind-rows of piles adjacent the ends of the ties, and the trailing shovels, having greater length, will displace the remainder of said ballast into a crib.

The invention exemplifies a ballasting tamping machine of the drop hammer type with apparatus for shoveling and feeding ballast deposited along the ends of the ties into the cribs so that it is not necessary to use manual labor for this purpose. This shoveling apparatus expedites the tamping operation because it feeds ballast into the cribs for tamping during the operation of the tamping elements.

The invention exemplifies means for shoveling ballast into the cribs which is controlled through the drop-head and tamping elements by the level of the packed ballast in the cribs and which remains idle until the ballast in the cribs is to be supplemented by additional ballast for filling them.

The fluid pressure devices impart quick strokes to the shovels for projecting the ballast into the cribs so that it will be distributedbetween the transverse center and the ends of the cribs.

The invention is not to be understood as restricted to the details described since these may be modified within the scope of the appended claims without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Paten is:

the combination with a portable frame, tamping elements, mechanism carried by the frame for operating the elements to tamp the ballast in the cribs between the ties; of shovels mounted on the frame to operate transversely of the railway track for displacing ballast from the road bed along the outer side of the track into position to be tamped in a crib by said elements, and means controlled by said mechanism for intermittently operating the shovels.

2. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, mechanism carried by the frame for operating the elements to tamp the ballast in the cribs between the ties; of shovels pivotally mounted on each side of the frame to operate transversely of the railway track for displacing ballast from the road bed along the outer sides of the track into position to be tamped in a crib by said elements, and means controlled by said mechanism for intermittently operating the shovels.

3. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, mechanism carried by the frame for operating theelements to tamp the ballast in the cribs between the ties; of a pair of shovels mounted on each side of the frame to operate transversely of the railway track for displacing ballast from the road bed along the outer side of the track into position to be tamped by said elements in cribs at the sides of a tie, and means controlled by said mechanism for intermittently operating the shovels.

4. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, mechanism carried by the frame for operating the elements to tamp the ballast in the cribs between the ties; of a pair of shovels mounted on each side of the frame, each pair being connected for conjoint pivotal movement for operating transversely of the railway track for displacing ballast from the road bed along the outer sides of the track into position to be tamped by said elements in the cribs, at the sides of a tie, and means controlled by said mechanism for intermittently operating the shovels.

5. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, and mechanism carried by the frame for operating the elements to tamp the ballast in the cribs between the ties; of shovels mounted on the frame to operate transversely of the railway track for displacing ballast from the road bed along the outer side of the track into position to be tamped by said elements in the cribs between ties, mechanism carried by the frame for intermittently operating the shovels, and means controlled by the depth of the strokes of said elements in the cribs for controlling the operation of the shovels.

6. In a ballast tamping machine for railways, the combination with a. portable frame, tamping elements, and mechanism carried .by the frame for operating the elements to tamp the ballast in the cribs between the ties; of shovels pivotally mounted on the frame to operate transversely of the railway track for displacing ballast from the road bed along the outer sides of the track into position to be tamped by said elements in the cribs between the ties, mechanism carried by the frame for intermittently operating the shovels, and means controlled by the depth of the strokes of said elements in the cribs for con- 1. In a ballast tamping machine for railways, I8 trolling the operation of the shovels.

7. In a ballast tamping machine for railways, the combination with a ortable frame, tampin elements, and mechanism carried by the frame for operating the elements to tamp the .allast in the cribs between the ties, of shovels mounted on the frame to operate transversely of the railway track for displacing ballast from the roadbed along the outside of the track into position to be tamped by said elements in the cribs between the sides, and means controlled by the operation of the mechanism for operating the tamping elements for controlling the shovel operating mechanism to render the shovels inoperative when the cribs have been filled with ballast.

8. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, and mechanism carried by the frame for operating the elements to tamp the ballast in the cribs between the ties; of shovels mounted on the frame to operate transversely of the rail way track for displacing ballast from the road bed along the outer side of the track into position to be tamped by said elements in the cribs between the ties, fluid pressure operable mechanism carried by the frame for intermittently operating the shovels, and means controlled by the length of the strokes of the tamping elements for controlling the operation of said mechanism.

9. In a ballast tampingmachine for railways, the combination with a portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and mechanism for imparting lifting strokes to the drop-rhead; of shovels mounted on the frame for displacing ballast on the road bed at the sides of the railway track transversely into position to be tamped by the elements in the cribs, mechanism carried by said frame for intermittently operating the shovels, and means for automatically controlling the operation of the shovel operating means to render the shovels operative during the up-strokes of the drop-head.

10. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and mechanism for imparting lifting strokes to the drop-head; of shovels mounted on the frame for displacing ballast on the road bed at the sides of the railway track transversely into position to be tamped by said elements in the cribs, mechanism for intermittently operating the shovels, and means controlled by the length of the strokes of the drop-head for controlling the operation of the shovel operating means.

of the strokes of the drop-head for controllingthe shovel operating means to operate the shovels to displace the ballast during the lifting strokes of said head.

12. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and

. l0 mechanism for imparting lifting strokes to the drop-head; of shovels mounted on the frame for displacing ballast on the road bed at the sides of the railway track transversely into position to be tamped by said elements in the cribs, mechanism carried'by the frame for intermittently operating the shovels, and means controlled by the length of the strokes of the drop-head for controlling the shovel operating means to operate the shovels during the lifting strokes of said head when .said head drops below a predetermined height and to render the shovel operating means inoperative when the ballast in the cribs has been packed.

13. In a ballast tamping machine for railways, the combination witha portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and mechanism for imparting lifting strokes to the drop-head; of shovels operatively mounted on the frame, for displacing ballast on the road bed at the side of the railway track into position to be tamped by said elements in the cribs,-fiuid pres- ;ure operable mechanism for intermittently operating the shovels, valve-means for controlling the operation of the fluid pressure operable means; and means on the drop-head for controlling the valve-means to operate the shovels.

14. In a ballast tamping machine for railways, the combination with a' portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and mechanism for imparting lifting strokes to the drop-head; of shovels operatively mounted on the frame for displacing ballast on the road bed at the side of the railway track into position to be tamped by said elements in the cribs, fluid pressure operable mechanism carried by the frame for intermittently operating the shovels, valvemeans for controlling the operation of the fluid pressure operable means; and means on the drophead for controlling the valve-means to operate the shovels during the lifting strokes of the drophead.

15. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and mechanism for .imparting lifting strokes to the drop-head; a pair of shovels pivotally mounted on each side of the frame for displacing ballast on the road bed at the sidesof the railway track transversely into position to be tamped by said elements in the cribs, fluid pressure operable mechanism mounted on the frame for intermittently operating the shovels, valve-means for controlling the operation of the fluid pressure operable means; and means on the drop-head-for controlling the valve-means to operate the shovels.

16. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, a drop-head carried by the frame and on which the tamping elements are mounted, and mechanism for imparting lifting strokes to the drop-head; of a pair of shovels operatively mounted on each side of the frame for displacing ballast on the road bed at the sides of the railway track transversely into position to be tamped by said elements in the cribs, spring-retracted fluid pressure operable mechanism carried by said frame for intermittently operating the shovels, valve-means for controlling the operation of the fluid pressure operable means; and adjustable means on the drop-head for controlling the valve- 9,4sa,7ce I means for operating the shovels during the lifting strokes of the drop-head.

17. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, and mechanism for imparting lifting strokes to said elements; of a pair of shovels mounted at one side of the frame, longitudinally of one another and transversely of the cribs at the sides of a tie, for displacing ballast on the road bed at the sides of the railway track into position to be tamped by said elements in the cribs, the shovels being operative and extended to successively displace into the cribs ballast at relatively diflerent distances above the roadbed, and means controlled by the lifting mechanism for conjointly operating the shovels.

18. In a ballast tamping machine for railways, the combination with a portable frame, tamping elements, and mechanism for imparting lifting strokes to the said elements; of a pair of pivotally and cc-axially supported shovels mounted at one side of the frame, longitudinally of one another and transversely of the cribs at the sides of a tie fordisplacing ballast on the road bed at the sides of the railway track into position to be tamped by said elements in the cribs. the shovels being operative. at different distances above the roadbed to successively displace ballast of diflerent heights into the cribs, and means controlled by the lifting mechanism for conjointly operating the shovels.

- FRANK H. PHILBRICK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PA'I'ENTS Number I Name Date 1,556,604 Jackson Oct. 13, 1925 20 2,082,594 Philbrick June 1, 1937 

